Process for increasing mass flow of an exhaust gas through a catalytic converter

ABSTRACT

Described herein is a process for increasing mass flow of an exhaust gas through a catalytic converter system for a vehicle. The process may comprise determining a centerline and corresponding cumulative centerline bend angle of a first catalytic converter system spanning from an inlet point at a first end of the catalytic converter systems exhaust pipe to an outlet point at a second end of the catalytic converter systems extension pipe. Once determined, the cumulative centerline bend angle may be increased by increasing an individual bend radius of at least one bend within the exhaust pipe and/or within the extension pipe.

CROSS REFERENCES AND PRIORITIES

This application claims priority from U.S. Provisional Application No.63/107,355 filed on 29 Oct. 2020 the teachings of which are incorporatedby reference herein in their entirety.

BACKGROUND

Modern vehicles make ubiquitous use of catalytic converter systems tocontrol the emission of toxic gases and pollutants in exhaust gas frominternal combustion engines. Use of catalytic converter systems isrequired by law in many countries, including the United States asproscribed by regulations from the U.S. Environmental Protection Agency(“EPA”) which require gasoline powered vehicles of 1975 model year ornewer to be equipped with a catalytic converter system.

The typical catalytic converter system comprises at least threecomponents. The first is a catalytic converter itself. Typically housedwithing a canister, the catalytic converter commonly includes a catalystsupport or substrate, washcoat—typically of aluminum oxide, titaniumdioxide, silicone dioxide, or combinations thereof—used as a catalystcarrier and to increase the surface area of the materials, and acatalyst which catalyzes a redox reaction with exhaust gases from aninternal combustion engine. Typical catalysts are often a mixture ofprecious metals with common examples including platinum, rhodium,cerium, iron, manganese, and nickel.

The second component is an exhaust pipe. The exhaust pipe connects oneend of the catalytic converter to the engine's exhaust manifold orexhaust header. This connection may occur through a flange and boltstyle connection or a slip-joint style connection.

The third component is an extension pipe. The extension pipe connectsthe opposite end of the catalytic converter to the vehicle's tailpipeand muffler system. This connection may occur through a flange and boltstyle connection or a slip-joint style connection.

Depending upon the type of engine, some catalytic converter systems mayrequire multiple catalytic converters, exhaust pipes, and/or extensionpipes. For instance, a vehicle equipped with an in-line four-cylinderengine may require a single catalytic converter connected to a singleexhaust manifold or exhaust header by a single exhaust pipe andconnected to a single tailpipe and muffler system by a single extensionpipe. However, a vehicle equipped with an eight-cylinder engine arrangedin a common V-8 configuration may require two catalytic converters witheach catalytic converter connected to a separate exhaust manifold orexhaust header by a separate exhaust pipe.

In practice, connecting the catalytic converter to the exhaust manifoldor exhaust header, and connecting the catalytic converter to thevehicle's muffler system often requires placing one or more bends in theexhaust pipe and/or extension pipe. These bends constrict the flow ofexhaust gases through the catalytic converter system. Such constrictionsoften result in decreased engine performance due to reduced mass flow ofthe engine's exhaust gases.

Many attempts have been made to improve engine performance in vehiclesequipped with catalytic converter systems. Often, these attempts arehampered by state or federal regulations—such as EPA regulations—whichrequire that the vehicle's catalytic converter be maintained in the samespatial position within the vehicle in order to maintain emissionscompliance.

The need exists, therefore, for an improved process for increasing massflow of exhaust gases through a catalytic converter system of a vehicle.

SUMMARY

A process for increasing mass flow of an exhaust gas through a catalyticconverter system for a vehicle is disclosed. The catalytic convertersystem may comprise at least a first exhaust pipe, a catalyticconverter, and a first extension pipe. The first exhaust pipe and/orfirst extension pipe may comprise at least one bend having a bendradius.

The process may comprise a step of characterizing a first inlet point, afirst outlet point, and an end plane of each individual bend of a firstcatalytic converter system. The process may also comprise a step ofdetermining a first centerline of the first catalytic converter system.The first centerline may be measured from the first inlet point to thefirst outlet point through a centerpoint of each individual end plane.The first centerline may comprise at least one centerline bendcorresponding to a bend of the at least one bend of the first exhaustpipe and or the first extension pipe. Each centerline bend will have acenterline bend angle.

The process may also comprise a step of measure a first baselinecumulative centerline bend angle of the first centerline. The processmay further comprise producing a subsequent catalytic converter systemhaving a first increased cumulative centerline bend angle. The firstincreased cumulative centerline bend angle may be achieved by increasingan individual bend radius of at least one bend within the first exhaustpipe and/or within the first extension pipe. The catalytic converter maybe maintained in substantially a same spatial position within thevehicle in both the first catalytic converter system and the subsequentcatalytic converter system.

In some embodiments, the catalytic converter system may further comprisea second exhaust pipe. The second exhaust pipe may comprise at least onebend having a bend radius. In such embodiments, the process may compriseas a further step characterizing a second inlet point and an end planeof each individual bend of the first catalytic converter system. Theprocess may also comprise as a further step determining a secondcenterline of the first catalytic converter system measured from thesecond inlet point to the first outlet point through a centerpoint ofeach individual end plane. The second centerline may comprise at leastone centerline bend corresponding to a bend of the at least one bend ofthe second exhaust pipe. As a further step, the process may alsocomprise measuring a second baseline cumulative centerline bend angle ofthe second centerline. As a further step, the process may also compriseproducing the subsequent catalytic converter system having a secondincreased cumulative centerline bend angle by increasing an individualbend radius of at least one bend within the second exhaust pipe.

In certain embodiments, the catalytic converter system may furthercomprise a second extension pipe. The second extension pipe may compriseat least one bend having a bend radius. In such embodiments, the processmay comprise the further step of characterizing a second outlet pointand an end plane of each individual bend of the first catalyticconverter system. The process may also comprise as a further stepdetermining a second centerline of the first catalytic converter systemmeasured from the first inlet point to the second outlet point through acenterpoint of each individual end plain. The second centerline maycomprise at least one centerline bend corresponding to a bend of the atleast one bend of the second extension pipe. As a further step, theprocess may also comprise measuring a second baseline cumulativecenterline bend angle of the second centerline. As a further step, theprocess may also comprise producing the subsequent catalytic convertersystem having a second increased cumulative centerline bend angle byincreasing an individual bend radius of at least one bend within thesecond extension pipe.

In some embodiments, the catalytic converter system may comprise asecond exhaust pipe, a second catalytic converter, and a secondextension pipe. The second exhaust pipe and/or second extension pipe maycomprise at least one bend having a bend radius. In such embodiments,the process may comprise the further step of characterizing a secondinlet point, a second outlet point, and an end plane of each individualbend of the first catalytic converter system. The process may alsocomprise as a further step determining a second centerline of the firstcatalytic converter system measured from the second inlet point to thesecond outlet point through a centerpoint of each individual end plane.The second centerline may comprise at least one centerline bendcorresponding to a bend of the at least one bend of the second exhaustpipe and/or the second extension pipe. As a further step, the processmay comprise measuring a second baseline cumulative centerline bendangle of the second centerline. As a further step, the process maycomprise producing the subsequent catalytic converter system having asecond increased cumulative centerline bend angle by increasing anindividual bend radius of at least one bend within the second exhaustpipe and/or within the second extension pipe.

In certain embodiments the first inlet point may be maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem. In some embodiments the first outlet point may be maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem. In certain embodiments, the first inlet point and the secondinlet point may both be maintained in substantially a same spatialposition within the vehicle in both the first catalytic converter systemand the subsequent catalytic converter system. In some embodiments thefirst outlet point and the second outlet point may both be maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem.

In some embodiments the process may comprise as a further stepincreasing an inside diameter of the first exhaust pipe. In certainembodiments the process may comprise as a further step increasing aninside diameter of the first extension pipe. In some embodiments theprocess may comprise as a further step increasing an inside diameter ofthe second exhaust pipe. In certain embodiments the process may compriseas a further step increasing an inside diameter of the second extensionpipe.

In some embodiments the catalytic converter system may comprise at leastone bung hole capable of receiving an oxygen feedback sensor. The atleast one bung hole may be maintained in substantially a same spatialposition within the vehicle in both the first catalytic converter systemand the subsequent catalytic converter system.

BRIEF DESCRIPTION OF FIGURES

FIG. 1 is a perspective view of one embodiment of a first catalyticconverter system for a vehicle.

FIG. 2 is a perspective view of one embodiment of a subsequent catalyticconverter system for a vehicle with an exhaust pipe and an extensionpipe overlaid onto a first catalytic converter system for a vehiclecomprising an exhaust pipe and an extension pipe.

FIG. 3 is a perspective view of one embodiment of a subsequent catalyticconverter system for a vehicle overlaid onto a first catalytic convertersystem for a vehicle.

FIG. 4 is a perspective view of one embodiment of a subsequent catalyticconverter system for a vehicle.

DETAILED DESCRIPTION

Disclosed herein is a process for increasing mass flow of a catalyticconverter system. The process is described below with reference to theFigures. As described herein and in the claims, the following numbersrefer to the following structures as noted in the Figures.

-   10A depicts a first catalytic converter system.-   10B depicts a subsequent catalytic converter system.-   20 depicts a first inlet point.-   30 depicts a first outlet point.-   50A depicts a first centerline.-   50B depicts a second centerline-   55 depicts a centerline bend.-   100 depicts a first exhaust pipe.-   110 depicts a first exhaust pipe first end.-   120 depicts a first exhaust pipe second end.-   130 depicts a flange.-   200 depicts a catalytic converter.-   210 depicts a catalytic converter inlet.-   220 depicts a catalytic converter outlet.-   300 depicts an extension pipe.-   310 depicts an extension pipe first end.-   320 depicts an extension pipe second end.

FIG. 1 depicts a perspective view of an embodiment of a first catalyticconverter system (10A). The first catalytic converter system may be anoriginal catalytic converter system—which is a catalytic convertersystem installed by the OEM manufacturer on the original vehicle—or itmay be an earlier installed aftermarket or replacement catalyticconverter system. As shown in FIG. 1 , the first catalytic convertersystem may comprise at least one catalytic converter (200) while in someembodiments the first catalytic converter system may comprise twocatalytic converters. Each catalytic converter may be connected to theengine's exhaust manifold or exhaust header (not shown) via an exhaustpipe such as the first exhaust pipe (100) shown in FIG. 2 . Accordingly,the first catalytic converter system may also comprise at least oneexhaust pipe while embodiments comprising two catalytic converters maycomprise two exhaust pipes. Each catalytic converter may also beconnected to the vehicle's muffler system (not shown) via an extensionpipe such as the first extension pipe (300) shown in FIG. 2 .Accordingly, the first catalytic converter system may also comprise atleast one extension pipe while embodiments comprising two catalyticconverters may comprise two extension pipes.

As shown in FIG. 1 , each catalytic converter will have a catalyticconverter inlet (210) and a catalytic converter outlet (220). Exhaustgases from the vehicle's engine enter at the catalytic converter inletand flow through the catalytic converter from the catalytic converterinlet through the catalytic converter outlet.

FIG. 2 shows that each first exhaust pipe (100) of the first catalyticconverter system will have a first exhaust pipe first end (110) and afirst exhaust pipe second end (120). When installed in a vehicle, thefirst exhaust pipe first end will connect to the engine's exhaustmanifold or exhaust header (not shown). This connection may occur via aflange which bolts to a corresponding flange (not shown) of the engine'sexhaust manifold or exhaust header, or via a slip joint as shown in FIG.2 in which the exhaust pipe has an inside diameter at the exhaust pipefirst end which is slightly greater than an outside diameter of theterminal end (not shown) of the engine's exhaust manifold or exhaustheader. This allows the exhaust pipe first end to slip over the terminalend of the engine's exhaust manifold or exhaust header. The exhaust pipefirst end may then be further secured to the exhaust manifold or exhaustheader by welding and/or via a clamp. Alternatively, the exhaust pipemay have an outside diameter at the exhaust pipe first end which isslightly less than an inside diameter of the terminal end (not shown) ofthe engine's exhaust manifold or exhaust header. This allows theterminal end of the engine's exhaust manifold or exhaust header to slipover the exhaust pipe first end.

When installed in a vehicle, the first exhaust pipe second end (120)will connect to the catalytic converter inlet (210). This connection mayoccur via a slip joint as shown in FIG. 2 in which the exhaust pipe hasan inside diameter at the exhaust pipe second end which is slightlygreater than an outside diameter of the catalytic converter inlet. Thisallows the exhaust pipe second end to slip over the catalytic converterinlet. Alternatively, the exhaust pipe may have an outside diameter atthe exhaust pipe second end which is slightly less than an insidediameter of the catalytic converter inlet. This allows the catalyticconverter inlet to slip over the exhaust pipe second end. The exhaustpipe second end may then be further secured to the catalytic converterinlet by welding and/or via a clamp. Alternatively, the connection mayoccur via a flange at the exhaust pipe second end which bolts to acorresponding flange at the catalytic converter inlet.

Each exhaust pipe may further comprise at least one exhaust pipe bend.In some embodiments, each exhaust pipe may comprise a plurality ofexhaust pipe bends. Each exhaust pipe bend will have an exhaust pipebend radius. The exact exhaust pipe bend radius of any individualexhaust pipe bend will vary based upon a number of factors including themake and model of the vehicle, and the type of engine. The bend radiusof an individual exhaust pipe bend may be expressed in terms relative tothe diameter of the exhaust pipe (D). In general, the exhaust pipe bendradius measurement of any individual exhaust pipe bend will be in arange selected from the group consisting of between 1×D and 7×D, between1×D and 5×D, between 1×D and 3×D, between 1.5×D and 7×D, between 1.5×Dand 5×D, between 1.5×D and 3×D, between 2×D and 7×D, between 2×D and5×D, and between 2×D and 3×D.

FIG. 2 further shows that each first extension pipe (300) will have afirst extension pipe first end (310) and a first extension pipe secondend (320). When installed in a vehicle, the first extension pipe firstend will connect to the catalytic converter outlet (220). Thisconnection may occur via a slip joint and clamp as shown in FIG. 2 inwhich the extension pipe has an inside diameter at the extension pipefirst end which is slightly greater than an outside diameter of thecatalytic converter outlet. This allows the extension pipe first end toslip over the catalytic converter outlet. Alternatively, the extensionpipe may have an outside diameter at the extension pipe first end whichis slightly less than an inside diameter of the catalytic converteroutlet. This allows the catalytic converter outlet to slip over theextension pipe first end. The extension pipe first end may then befurther secured to the catalytic converter outlet by welding and/or viaa clamp. Alternatively, this connection may occur via a flange at theextension pipe first end which bolts to a corresponding flange at thecatalytic converter outlet.

When installed in a vehicle, the first extension pipe second end (320)will usually connect to the vehicle's tailpipe and muffler system (notshown). This connection may occur via a slip joint in which theextension pipe has an inside diameter at the extension pipe second endwhich is slightly greater than an outside diameter of the tailpipe orthe muffler inlet port (not shown). This allows the extension pipesecond end to slip over the tailpipe or the muffler inlet port.Alternatively, the extension pipe may have an outside diameter at theextension pipe second end which is slightly greater than an insidediameter of the tailpipe or the muffler inlet port. This allows the tailpipe or muffler inlet port to slip over the extension pipe second end.The extension pipe second end may then be further secured to thetailpipe or the muffler inlet port by welding and/or via a clamp.Alternatively, the connection may occur via a flange at the extensionpipe second end which bolts to a corresponding flange at the tailpipe ormuffler inlet port.

Each extension pipe may further comprise at least one extension pipebend as shown in FIG. 2 . In some embodiments, each extension pipe maycomprise a plurality of extension pipe bends. Each extension pipe bendwill have an extension pipe bend radius. The exact extension pipe bendradius of any individual extension pipe bend will vary based upon anumber of factors including the make and model of the vehicle, and thetype of engine. In general, the extension pipe bend radius measurementof any individual extension pipe bend will be in the range of between1×D and 7×D, between 1×D and 5×D, between 1×D and 3×D, between 1.5×D and7×D, between 1.5×D and 5×D, between 1.5×D and 3×D, between 2×D and 7×D,between 2×D and 5×D, and between 2×D and 3×D.

The first catalytic converter system (10A) will also have a firstcenterline (50) as shown in FIG. 2 . The first centerline will run alongthe central axis of the exhaust pipe(s), catalytic converter(s), andextension pipe(s) from a first inlet point (20) located at the exhaustpipe first end (110) to a first outlet point (30) located at theextension pipe second end (320). One of ordinary skill will recognizethat, in embodiments comprising more than one catalytic converter, morethan one exhaust pipe, and/or more than one extension pipe the firstcatalytic converter system will have multiple first centerlines. Forexample, when the first catalytic converter system comprises two exhaustpipes with each exhaust pipe connected to one of two catalyticconverters, there will be two first centerlines with one of the firstcenterlines corresponding to the first exhaust pipe and first catalyticconverter, and the other first centerline corresponding to the secondexhaust pipe and second catalytic converter.

In most embodiments, the first centerline (and optionally the secondcenterline) will not be a straight line, but will comprise one or morecenterline bends (55) with each centerline bend corresponding to anexhaust pipe bend or an extension pipe bend. Each centerline bend of thefirst centerline (and optionally the second centerline) will have anindividual centerline bend angle. The exact angle measurement of anyindividual centerline bend of the first centerline (and optionally thesecond centerline) will vary based upon a number of factors includingthe make and model of the vehicle, and the type of engine. In general,the centerline bend angle measurement of any individual centerline bendof the first centerline (and optionally the second centerline) will bein a range selected from the group consisting of between 90° and 179°,between 90° and 160°, between 90° and 145°, between 90° and 120°,between 120° and 179°, between 120° and 160°, between 120° and 145°,between 145° and 179°, between 145° and 160°, and between 160° and 179°.

FIG. 3 shows an example of a subsequent catalytic converter system (10B)made via the process disclosed herein. In general, the process willbegin by characterizing a first inlet point (20), a first outlet point(30), and an end plane of each individual bend of the first catalyticconverter system (10A as shown in FIG. 1 ). The first inlet point andfirst outlet point will correspond to the first exhaust pipe first end(110) and the first extension pipe second end (320) respectively. Theend plane will be the plane perpendicular to the length of the pipe ateach of the opposing ends of the individual bend.

The first inlet point (20), first outlet point (30), and end planes maybe characterized based off of a physical embodiment of the firstcatalytic converter system (10A). In alternative embodiments, the firstinlet point and first outlet point may be characterized using CAD/CAMsoftware based off of a digital three-dimensional model of the firstcatalytic converter systems. In some embodiments, the digitalthree-dimensional model may be provided by the factory vehiclemanufacturer. In other embodiments, the digital three-dimensional modelmay be produced by the user prior to characterizing the first inletpoint and first outlet point using three-dimensional scanning technologysuch as a FARO® Quantum FAROARM® & Scanarm Series measuring toolavailable from FARO Technologies, Inc. of Lake Mary, Fla., U.S.A.

Once the first inlet point, second inlet point, and end planes have beencharacterized, they may be used to determine the first centerline (50A)of the first catalytic converter system (10A). As described herein, thefirst centerline will be measured from the first inlet point to thefirst outlet point with the first centerline intersecting each end planeof each individual bend at the center point of said end planes. Asdescribed herein, the first centerline will comprise at least onecenterline bend (55) corresponding to a bend of the at least one bend ofthe first exhaust pipe and/or the first extension pipe with eachcenterline bend having an individual centerline bend angle. Thecenterline bend angle measurement of any individual centerline bend ofthe first centerline will be in the range of between 90° and 179°,between 90° and 160°, between 90° and 145°, between 90° and 120°,between 120° and 179°, between 120° and 160°, between 120° and 145°,between 145° and 179°, between 145° and 160°, and between 160° and 179°.

The first centerline (50A) may be determined based off of a physicalembodiment of the first catalytic converter system (10A). Alternatively,the first centerline may be determined using CAD/CAM software based offof a digital three-dimensional model of the first catalytic convertersystems obtained as disclosed herein.

Once the first centerline has been determined, the process may involvemeasuring a first baseline cumulative centerline bend angle of the firstcenterline (50A). The first baseline cumulative centerline bend anglewill be the sum of the centerline bend angle measurement of eachindividual centerline bend of the first centerline.

After measuring the first baseline cumulative centerline bend angle ofthe first centerline (50A) of the first catalytic converter system(10A), the cumulative centerline bend angle may be increased to producethe subsequent catalytic converter system (10B). This may beaccomplished by increasing an individual bend radius of at least onebend within the first exhaust pipe and/or within the first extensionpipe. For instance, the bend radius of one bend in the first exhaustpipe and/or within the first extension pipe in the first catalyticconverter system may be 3×D, while in the subsequent catalytic convertersystem the bend radius of the same bend may be increased to 2×D. Thebend radius may be increased by bending the existing exhaust pipe orextension pipe to increase the bend radius, or by fabricating a newexhaust pipe or extension pipe (or section thereof) having an increasedbend radius. By increasing the individual bend radius of at least onebend, the cumulative centerline bend angle may be increased such thatthe first centerline of the subsequent catalytic converter system has afirst increased cumulative centerline bend angle.

In embodiments comprising a second exhaust pipe, a second catalyticconverter, and/or a second extension pipe, the process may involveincreasing the cumulative centerline bend angle of the secondcenterline. In such embodiments, the process may involve characterizinga second inlet point, a second outlet point, and/or an end plane of eachindividual bend within the second exhaust pipe and/or the secondextension pipe of the first catalytic converter system (10A) with thesecond inlet point corresponding to the second exhaust pipe first endand the second outlet point corresponding to the second extension pipesecond end. The end plane will be the plane perpendicular to the lengthof the pipe at each of the opposing ends of the individual bend.

In embodiments with a second centerline, after characterizing the secondinlet point, the second outlet point, and/or the end planes, the processmay involve determining the second centerline. Depending upon theconfiguration (number of exhaust pipes, number of catalytic converters,and number of extension pipes) the second centerline may be measuredfrom the first inlet point to the second outlet point, from the secondinlet point to the first outlet point, or from the second inlet point tothe second outlet point. Regardless, the second centerline willintersect each end plane of each individual bend within the secondexhaust pipe and/or the second extension pipe at the center point ofsaid end planes.

As described herein, the second centerline will comprise at least onecenterline bend (55) corresponding to a bend of the at least one bend ofthe second exhaust pipe and/or the second extension pipe with eachcenterline bend having an individual centerline bend angle. Thecenterline bend angle measurement of any individual centerline bend ofthe second centerline will be in the range of between 90° and 179°,between 90° and 160°, between 90° and 145°, between 90° and 120°,between 120° and 179°, between 120° and 160°, between 120° and 145°,between 145° and 179°, between 145° and 160°, and between 160° and 179°.

Once the second centerline has been determined, the process may involvemeasuring a second baseline cumulative centerline bend angle of thesecond centerline. The second baseline cumulative centerline bend anglewill be the sum of the centerline bend angle measurement of eachindividual centerline bend of the second centerline.

After measuring the second baseline cumulative centerline bend angle ofthe second centerline of the first catalytic converter system (10A), thecumulative centerline bend angle may be increased to produce thesubsequent catalytic converter system (10B). This may be accomplished byincreasing an individual bend radius of at least one bend within thesecond exhaust pipe and/or within the second extension pipe. Forinstance, the bend radius of one bend in the second exhaust pipe and/orwithin the second extension pipe in the first catalytic converter systemmay be 3×D, while in the subsequent catalytic converter system the bendradius of the same bend may be increased to 2×D inches. The bend radiusmay be increased by bending the existing exhaust pipe or extension pipeto increase the bend radius, or by fabricating a new exhaust pipe orextension pipe (or section thereof) having an increased bend radius. Byincreasing the individual bend radius of at least one bend, thecumulative centerline bend angle may be increased such that the secondcenterline of the subsequent catalytic converter system has a secondincreased cumulative centerline bend angle.

It is believed that increasing the cumulative centerline bend angle(s)by increasing the individual bend radius of at least one bend within theexhaust pipe(s) and/or extension pipe(s) will reduce or eliminateconstrictions within the catalytic converter system. Reducing oreliminating these constrictions is believed to increase the mass flow ofthe engine's exhaust system leading to improved engine performance asindicated by one or more of increased engine horsepower, increasedengine torque, and/or audible engine sound.

FIG. 3 shows a perspective view of the subsequent catalytic convertersystem (10B) overlaid onto the first catalytic converter system (10A).As can be seen in FIG. 3 , the centerline(s) of the subsequent catalyticconverter system have an increased cumulative centerline bend angle whencompared to the cumulative centerline bend angle of the first catalyticconverter system.

Throughout the process, it is preferred to maintain the catalyticconverter(s) (200) in substantially a same spatial position within thevehicle in both the first catalytic converter system (10A) and thesubsequent catalytic converter system (10B) as shown in FIG. 3 . Morepreferably, the catalytic converter(s) are maintained in the exact samespatial position within the vehicle in both the first catalyticconverter system and the subsequent catalytic converter system. Thespatial position refers to the location of the catalytic converter(s)along an x,y,z axis coordinate system.

In some embodiments, the inlet point(s) (20) are maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system (10A) and the subsequent catalyticconverter system (10B) as shown in FIG. 3 . Preferably, the inletpoint(s) are maintained in the exact same spatial position within thevehicle in both the first catalytic converter system and the subsequentcatalytic converter system. The spatial position refers to the locationof the inlet point(s) along an x,y,z axis coordinate system.

In some embodiments, the outlet point(s) (30) are maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system (10A) and the subsequent catalyticconverter system (10B) as shown in FIG. 3 . Preferably, the inlet andoutlet point(s) are maintained in the exact same spatial position withinthe vehicle in both the first catalytic converter system and thesubsequent catalytic converter system. The spatial position refers tothe location of the inlet and outlet point(s) along an x,y,z axiscoordinate system.

In many catalytic converter systems, the first catalytic convertersystem will comprise one or more oxygen feedback sensors. These oxygenfeedback sensors will be attached at a position along the catalyticconverter system—often by placing the oxygen feedback sensor into a bunghole which is capable of receiving an oxygen feedback sensor. Theprocess may comprise maintaining the at least one—and preferably all—ofthe bung hole(s) in substantially the same or exactly the same spatialposition within the vehicle in both the first catalytic converter system(10A) and the subsequent catalytic converter system (10B). The spatialposition refers to the location of the bung hole(s) along an x,y,z axiscoordinate system.

Preferably, both the inlet point(s) (20) and the outlet point(s) (30)are maintained in substantially a same or exactly a same spatialposition within the vehicle in both the first catalytic converter system(10A) and the subsequent catalytic converter system (10B) as shown inFIG. 3 . The spatial position refers to the location of the inletpoint(s) and outlet point(s) along an x,y,z axis coordinate system.

In some embodiments, the mass flow of an exhaust gas may be furtherincreased by increasing an inside diameter of one or more of the exhaustpipe(s) (100) and/or extension pipe(s) (300) during the process.Preferably, the process may comprise increasing an inside diameter ofeach of the exhaust pipe(s) and extension pipe(s). It is believed thatincreasing the inside diameter of one or more (or all) of the exhaustpipe(s) and extension pipe(s) will reduce or eliminate constrictionswithin the catalytic converter system. Eliminating these constrictionsis believed to increase the mass flow of the engine's exhaust systemleading to improved engine performance as indicated by one or more ofincreased engine horsepower, increased engine torque, and/or audibleengine sound.

What is claimed is:
 1. A method for increasing mass flow of an exhaustgas through a catalytic converter system for a vehicle, said catalyticconverter system comprising at least a first exhaust pipe (100), a firstcatalytic converter (200), and a first extension pipe (300); said firstexhaust pipe and/or said first extension pipe comprising at least onebend having a bend radius; said method comprising the steps of:characterizing a first inlet point (20), a first outlet point (30), andan end plane of each individual bend of a first catalytic convertersystem (10A); determining a first centerline (50A) of the firstcatalytic converter system measured from the first inlet point to thefirst outlet point through a centerpoint of each individual end plane,said first centerline comprising at least one centerline bend (55)corresponding to a bend of the at least one bend of the first exhaustpipe and/or the first extension pipe, each centerline bend having acenterline bend angle; measuring a first baseline cumulative centerlinebend angle of the first centerline; and producing a subsequent catalyticconverter system (10B) having a first increased cumulative centerlinebend angle by increasing an individual bend radius of at least one bendwithin the first exhaust pipe and/or within the first extension pipe byany one or more of the following: bending the first exhaust pipe,bending the first extension pipe, fabricating a new first exhaust pipeor a section of a new first exhaust pipe, and/or fabricating a new firstextension pipe or a section of a new first extension pipe; and whereinthe catalytic converter is maintained in substantially a same spatialposition within the vehicle in both the first catalytic converter systemand the subsequent catalytic converter system.
 2. The method of claim 1,wherein the catalytic converter system further comprises a secondexhaust pipe comprising at least one bend having a bend radius, andwherein the method comprises the further steps of: characterizing asecond inlet point and an end plane of each individual bend of the firstcatalytic converter system; determining a second centerline of the firstcatalytic converter system measured from the second inlet point to thefirst outlet point through a centerpoint of each individual end plane,said second centerline comprising at least one centerline bendcorresponding to a bend of the at least one bend of the second exhaustpipe; measuring a second baseline cumulative centerline bend angle ofthe second centerline; and producing the subsequent catalytic convertersystem having a second increased cumulative centerline bend angle byincreasing an individual bend radius of at least one bend within thesecond exhaust pipe by any one or more of the following: bending thesecond exhaust pipe, and/or fabricating a new second exhaust pipe or asection of a new second exhaust pipe.
 3. The method of claim 1, whereinthe catalytic converter system further comprises a second extension pipecomprising at least one bend having a bend radius, and wherein themethod comprises the further steps of: characterizing a second outletpoint and an end plane of each individual bend of the first catalyticconverter system; determining a second centerline of the first catalyticconverter system measured from the first inlet point to the secondoutlet point through a centerpoint of each individual end plane, saidsecond centerline comprising at least one centerline bend correspondingto a bend of the at least one bend of the second extension pipe;measuring a second baseline cumulative centerline bend angle of thesecond centerline; and producing the subsequent catalytic convertersystem having a second increased cumulative centerline bend angle byincreasing an individual bend radius of at least one bend within thesecond extension pipe by any one or more of the following: bending thesecond extension pipe, and/or fabricating a new second extension pipe ora section of a new second extension pipe.
 4. The method of claim 1,wherein the catalytic converter system further comprises a secondexhaust pipe, a second catalytic converter, and a second extension pipe;said second exhaust pipe and/or said second extension pipe comprising atleast one bend having a bend radius; and wherein the method comprisesthe further steps of: characterizing a second inlet point, a secondoutlet point, and an end plane of each individual bend of the firstcatalytic converter system; determining a second centerline of the firstcatalytic converter system measured from the second inlet point to thesecond outlet point through a centerpoint of each individual end plane,said second centerline comprising at least one centerline bendcorresponding to a bend of the at least one bend of the second exhaustpipe and/or the second extension pipe; measuring a second baselinecumulative centerline bend angle of the second centerline; and producingthe subsequent catalytic converter system having a second increasedcumulative centerline bend angle by increasing an individual bend radiusof at least one bend within the second exhaust pipe and/or within thesecond extension pipe by any one or more of the following: bending thesecond exhaust pipe, bending the second extension pipe, fabricating anew second exhaust pipe or a section of a new second exhaust pipe,and/or fabricating a new second extension pipe or a section of a newsecond extension pipe.
 5. The method of claim 1, wherein the first inletpoint is maintained in substantially a same spatial position within thevehicle in both the first catalytic converter system and the subsequentcatalytic converter system.
 6. The method of claim 1, wherein the firstoutlet point is maintained in substantially a same spatial positionwithin the vehicle in both the first catalytic converter system and thesubsequent catalytic converter system.
 7. The method of claim 2, whereinthe first inlet point and the second inlet point are both maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem.
 8. The method of claim 7, wherein the first outlet point ismaintained in substantially a same spatial position within the vehiclein both the first catalytic converter system and the subsequentcatalytic converter system.
 9. The method of claim 3, wherein the firstinlet point and the second inlet point are both maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem.
 10. The method of claim 9, wherein the first outlet point andthe second outlet point are both maintained in substantially a samespatial position within the vehicle in both the first catalyticconverter system and the subsequent catalytic converter system.
 11. Themethod of claim 1, wherein the method comprises the further step of:increasing an inside diameter of the first exhaust pipe.
 12. The methodof claim 1, wherein the method comprises the further steps of:increasing an inside diameter of the first extension pipe.
 13. Themethod of claim 2, wherein the method comprises the further step of:increasing an inside diameter of the second exhaust pipe.
 14. The methodof claim 3, wherein the method comprises the further step of: increasingan inside diameter of the second extension pipe.
 15. The method of claim1, wherein the catalytic converter system comprises at least one bunghole capable of receiving an oxygen feedback sensor, and the at leastone bung hole is maintained in substantially a same spatial positionwithin the vehicle in both the first catalytic converter system and thesubsequent catalytic converter system.
 16. The method of claim 2,wherein the first inlet point is maintained in substantially a samespatial position within the vehicle in both the first catalyticconverter system and the subsequent catalytic converter system.
 17. Themethod of claim 3, wherein the first inlet point is maintained insubstantially a same spatial position within the vehicle in both thefirst catalytic converter system and the subsequent catalytic convertersystem.
 18. The method of claim 4, wherein the first inlet point and thesecond inlet point are both maintained in substantially a same spatialposition within the vehicle in both the first catalytic converter systemand the subsequent catalytic converter system.
 19. The method of claim5, wherein the first outlet point is maintained in substantially a samespatial position within the vehicle in both the first catalyticconverter system and the subsequent catalytic converter system.
 20. Themethod of claim 19, wherein the first outlet point and the second outletpoint are both maintained in substantially a same spatial positionwithin the vehicle in both the first catalytic converter system and thesubsequent catalytic converter system.